Sequencing devices for ticket tacker sewing machines

ABSTRACT

A SEWING MACHINE HAS BEEN PROVIDED WITH IMPROVED SEQUENCING MEANS FOR SEWING A MATERIAL SUCH AS A GARMENT TAG TO A FABRIC. THE SEWING MACHINE WHICH CONVENTIONALLY HAS MEANS FOR LIFTING A PRESSER FOOT FROM ITS NORMAL DOWN POSITION, MEANS FOR INITIATING A STITCHING CYCLE, MEANS FOR SEWING SAID PREDETERMINED NUMBER OF STITCHES AND MEANS FOR TERMINATING THE STITCHING CYCLE IS MODIFIED WITH A COMBINATION COMPRISING MEANS FOR HOLDING THE PRESSER FOOT IN AN AUTOMATICALLY DISENGAGED UP-POSITIONS, AND MEANS FOR INITIATING A STITCHING CYCLE AND WHICH LAST MEANS COMPRISE (A) MEANS FOR DEACTIVATING THE MEANS FOR HOLDING SAID PRESSER FOOT IN THE UP-POSITION, AND (B) MEANS FOR SEQUENTIALLY INTERLOCKING: A PRESSER FOOT ENGAGING MEANS, WITH THE STITCH SEWING MEANS, WITH THE STITCHING CYCLE TERMINATING MEANS. THE STITCHING CYCLE TERMINATING MEANS INCLUDE MEANS FOR REACTIVATING THE MEANS FOR HOLDING THE PRESSER FOOT IN THE UP-POSITION.

March 23, 1971 A. G. BEAZLEY SEQUENCING DEVICES FOR TICKET TACKER SEWINGMACHINES Filed April 1, 1969 Tia l g 28 32 /2 y 9 38 o) o E? I Q Q 37 O43 Q71: I M 44 43 L f -.23|"' 32 i L J Bu c ==f 4' rlZOv 1 AC 34 E1 M4)WW1} ATTOR YS lzgsmon flubg y .Beuzley United States Patent Oflice US.Cl. 112-67 1 Claim ABSTRACT OF THE DISCLOSURE A sewing machine has beenprovided with improved sequencing means for sewing a material such as agarment tag to a fabric. The sewing machine which conventionally hasmeans for lifting a presser foot from its normal down position, meansfor initiating a stitching cycle, means for sewing said predeterminednumber of stitches and means for terminating the stitching cycle ismodified with a combination comprising means for holding the presserfoot in an automatically disengaged up-position; and means forinitiating a stitching cycle and which last means comprise (a) means fordeactivating the means for holding said presser foot in the up-position;and (b) means for sequentially interlocking: a presser foot engagingmeans; with the stitch sewing means; with the stitching cycleterminating means. The stitching cycle terminating means include meansfor reactivating the means for holding the presser foot in theup-position.

This invention relates to a cyclically operated sewing machine; moreparticularly this invention pertains to a pattern cam operated sewingmachine stitching a predetermined number of stitches such as at a cornerof a tag and wherein the pattern cam controlled operation is modified toeliminate operator fatigue and errors causing machine malfunction.

PRIOR ART Automatic tacking machines are widely known and used in theindustry to affix to a garment various identification tags, labels,markings and the like. The sewing machines employed for this purpose aresingle-thread chain stitch machines having a mechanism for moving thematerial with the tag from each stitch position to the next in apredetermined pattern and regulating the number of stitches in eachdiscrete stitch pattern. These machines are of the cylinder-bedconstruction and have a pattern cam disk or wheel mounted on the side ofthe arm at the hollow standard of the machine. A drive shaft journaledin the standard is provided. On this shaft at the balance wheel end ofit, a stop motion device coupled to a clutch is generally employed. Thepattern cam is mounted on a short, transverse shaft (to the mainshaft)driven from the main or drive shaft by a worm and a Worm Wheel. Besidesthe pattern forming cam groove, the pattern cam has other cam surfaceswith cam follower mechanisms. These follower mechanisms through variouslevers and linkages activate mechanisms provided for stopping themachine, nipping the thread below the throat plate, or severing thethread, etc. A representative machine of this type is a Singer 114-31sewing machine or a sewing machine illustrated in US. Pat. 2,938,477.

In sewing a tag to a garment, each discrete stitch grouping is carriedout in an identical sequence. For example, a garment tag is placed on afabric to which the tag is to be atfixed. The operator raises a presserfoot with a left foot pedal activated mechanical device thus overcominga spring associated with the presser foot which holds the presser footin its normal down position. Thereafter, the operator lifts the leftfoot which releases the presser foot and then momentarily depressesanother foot pedal with 3,572,267 Patented Mar. 23, 1971 the right footreleasing the pedal as soon as the machine starts to sew. Once themachine is started, it is provided with mechanical clutch latching meanswhich do not release until the end of the stitching cycle. When themachine stops the operator depresses the left foot pedal which lifts thepresser foot and removes the workpiece and places it under the needle atanother corner of the tag to repeat the sequence.

Although other machines operated at higher speeds are known, in general,these cam controlled sewing machins run at about 1500 rpm. and will haveas a representative number 14 stitches for each discrete stitch groupwhich is about .6 second per sewing cycle for each stitch grouping. Ascan be envisioned, the operator must be well coordinated and veryskilled at rapid and precisely timed foot operation and able to timeeach activation without overlapping the same with another, possibly,destructive operation. Moreover, the continuous operation of a sewingmachine with these mechanical controls tires an operator both physicallyand mentally leading to degradation in quality and output and increasingthe statistical incidence of accidents.

DISCLOSE-D SEWING MACHINE It has now been found that if the cyclicalsewing machine is provided with a new combination of properly sequenced,interrelated, and interdependent means for carrying out the cyclicaloperation in place of the prior art means calling for a differentinterrelationship and interdependence of same and different means, thenunobvious results in lessening operator fatigue, improving production,lessening machine wear etc. are observed because of the elimination ofsteps and improved sequencing achieved with the novel combination. Inthe accompanying drawings which illustrate a preferred form of thisinvention:

FIG. 1 is a front perspective view of the sewing machine having thisinvention applied thereto; and

FIG. 2 represents an electro-pneumatic circuit interrelated withmechanical means which activate the sewing machine in accordance withthe invention herein.

In reference to the figures and wherein the same elements are designatedby the same numbers, FIG. 1 illustrates the so-called cylinder-bedsewing machine having a frame which includes a free ended worksupporting bed 11 which admits tubular articles such as pants. The bed11 is formed to extend from hollow vertical standard 12 formed with abracket arm 13 which overlies the bed.

Further, in reference to FIG. 1, the cylinder bed has on the top,work-support surface a feed plate 21, a throat plate 22, and a presserfoot 23 or as it is sometimes called an upper jaw of a work clamp, thelower jaw being the feed plate 21. At the end of the bed and adjacentthe standard, a forward projecting lever interconnects with other levers(not shown), in the conventional manner, the feed plate 21 and thepattern cam 25 to define via the cam follower mechanism the movement ofthe feed plate 21 and thus the tag and fabric when appropriatelyclamped. This movement is necessary to define the stitch pattern.

Overlaying the feed plate levers is the presser foot lever 26 with aprojecting finger 27. This finger is in turn engaged by the presser footlifting bar 28 having a second pin 29 engaging the finger 27. In orderto bias the presser foot toward and away from the workpiece, the presserfoot is spring held in the clamped position by a spring 30 which isinterconnected with the presser foot lever at a pivot (or fulcrum) point31 with the feed plate lever. The presser foot is lifted or biased via apresser foot bar lifting lever 32. Lever 33 forms part of a cam followermechanism (which is not shown) and it operates a lower thread nipper(not shown).

A thread breaker bar 34 is interconnected with a conventional threadbreaker or cutting mechanism under the throat plate (not shown). Thethread breaker bar is activated by a conventional cam follower mechanism(not shown) interconnected with a cam surface on the pattern cam disk25.

The pattern cam disk 25 is interconnected through a short shaft 36 and aworm gear on the shaft to a worm on the main shaft 37 which is journaledin the frame. The main drive shaft may be provided with a stop motiondevice either through an appropriately designed device mounted on theshaft capable of stopping the machine by means of the motor driving theshaft with the needle bar and needle in the tip-position or a stopmotion device operated from the pattern cam disk 25 by a cam followermechanism and interconnected to the drive shaft at the balance wheel 38end thereof. As the stop motion devices are well known in the art, thesedevices have not been shown.

OPERATION OF THE DISCLOSED SEWING MACHINE Whereas in the prior artdevices the cyclical operation starts with the presser foot resting in aclamped relationship on the feed plate, according to the presentinvention, upon activation of a master switch, the presser foot islifted by a solenoid valve admitting fluid under pressure to a fluidwork device e.g. a pneumatic cylinder 39. Explaining the novelsequencing means used therewith and in reference to FIG. 2, when thesewing machine is in the stop position, i.e. at the beginning of cycle,(or as further explained herein when provided with a training device),all switches and relay 40 are in the position shown in FIG. 2. Upondepressing the foot switch 41, which is a two contact switch, thepresser foot solenoid valve 42 is de-energized, the presser foot 23 goesdown because it is spring actuated. The presser foot lever 32 in turnactivates a microswitch 43 designated as such in FIG. 2 and alsoidentified in FIG. 1 with the same numeral. The employment of amicroswitch 43 is a sequencing safeguard which has been found to beuseful for preventing the clutch from being actuated unless the presserfoot is down. The A section of the foot switch energizes the clutchcylinder solenoid valve 44 which in turn operates a fluid work device,e.g. an air cylinder 45 identified in FIG. 1. This work devicemechanically latches by conventional means the sewing machine in astitching or sewing cycle. The relay 40 is energized by B section of thefoot switch and it is latchingly held by its own holding contactsthrough the ground or return line of thread breaker bar microswitchdesignated as 46 in FIG. 2. The circuit for switch 46 has also beenidentified in FIG. 2: and the switch is identified with the same numeralin FIG. 1. This latching action prevents the presser foot solenoid valvefrom being energized when the operator releases the foot switch beforethe machine has finished its sewing cycle governed by the pattern camthereafter. Before the machine finishes its complete cycle forming thediscrete stitch grouping, but after it has finished its 14 stitch cycle,the needle and bobbin threads are automatically trimmed by the threadtrimmer (not shown) which is activated by the thread breaker bar 34. Aspreviously explained, the thread breaker bar is activated by a camfollower mechanism from the pattern cam disk. The thread breaker bar 34makes a lateral oscillation during the thread trimming operation.Consequently, this mechanical feature has been used to trigger theswitch 46 by means of pin 35 on the bar. The momentary back and forthmovement of the bar de-energizes the relay 40 which in turn causes thepresser foot to lift and end the cycle, i.e. allows the next discretestitch group to be formed immediately.

An additional aspect of this invention is an aid in training newoperators. This aspect of the invention is illustrated in FIG. 2 whereinthe foot switch 41 has been provided with a two stage, interruptibleswitch. The dotted portion of the diagram illustrates this feature whichoperates as follows. A foot switch is provided with a first stage, i.e.the dotted-section and a second stage consisting of A and B. If theoperator presses down for a partial foot switch travel, only the firststage switch is actuated.

This stage controls lowering and lifting of the presser footindependently of the other means to initiate and control the sequencingof the stitching operation. To check workpiece positioning, an unskilledoperator can lower the presser foot before starting sewing. If theoperator wishes to lift the presser foot, it allows the spring operatedfoot pedal to return and energize presser foot solenoid valve 42.However, if the operator is satisfied that the workpiece is properlypositioned, pressing down harder starts the machine through theengagement of A and B parts of the switch.

After a short training period, the operator no longer needs to make useof this feature and presses hard enough to actuate only the A and Bparts of the switch with the first stage being eliminated, or if it isdesired by retaining the first stage and pressing down to actuate bothfirst and second switches in one motion.

What is claimed is:

1. A control system for a sewing machine comprising a first solenoid forcontrolling a presser foot, said solenoid being normally energized whenin a first position for maintaining said presser foot in an openposition;

actuation means connected to a thread cutting mechanism;

a second solenoid for initiating and maintaining a stitching cycle whichincludes operation of the thread cutting mechanism near the end of thecycle;

a two position latching relay for energizing said first solenoid when insaid first position;

a manually operated switch for operating said relay to latch it in asecond position thereby de-energizing said first solenoid and closingthe presser foot, and for energizing said second solenoid wherebyinitiating and maintaining the stitching cycle;

a first electrical switching means connected in series between saidmanually operated switch and said second solenoid, said first switchmeans being operated by said presser foot for providing a closed circuitbetween said manually operated switch and said second solenoid when saidpresser foot is in the down position; and

a second electrical switching means connected to said latching relay forreturning said latching relay to its first position, said secondswitching means, being activated by said actuation means upon operationof the thread cutting mechanism at the end of the sewing cycle.

References Cited UNITED STATES PATENTS 2,764,112 9/1956 Happe 112-672,928,362 3/1960 Benink et a1. 112-67 3,157,261 11/1964 Bono ll267X3,245,369 4/1966 Myska 112-67 3,298,341 1/1967 BOnis l12219 H. HAMPTONHUNTER, Primary Examiner

